We collected major stimulus-driven action [1]} (the stop, move, right lane change, and left lane change) instances from each of the videos. Lane changes include right manoeuvres to a right adjacent lane, and left manoeuvres to a left adjacent lane. We ensured that all comments of the driver related to these actions were part of the collected video instances; see Figure REF  for sample frames from the videos. We watched the video instances repeatedly for the four actions, we discovered that the driver in most cases made explanations in the following order: (i) announce observations, (ii) announce plans (with or without reference to road rules), and (iii) make general remarks.
